From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52168) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gG1LW-0007we-Hw for qemu-devel@nongnu.org; Fri, 26 Oct 2018 08:36:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gG1LS-00087z-Iy for qemu-devel@nongnu.org; Fri, 26 Oct 2018 08:36:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46484) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gG1LS-000878-Cz for qemu-devel@nongnu.org; Fri, 26 Oct 2018 08:36:06 -0400 From: P J P Date: Fri, 26 Oct 2018 18:03:58 +0530 Message-Id: <20181026123358.2554-1-ppandit@redhat.com> Subject: [Qemu-devel] [PATCH v2] ppc/pnv: check size before data buffer access List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Qemu Developers Cc: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= , Moguofang , David Gibson , Alexander Graf , Benjamin Herrenschmidt , Prasad J Pandit From: Prasad J Pandit While performing PowerNV memory r/w operations, the access length 'sz' could exceed the data[4] buffer size. Add check to avoid OOB access. Reported-by: Moguofang Signed-off-by: Prasad J Pandit --- hw/ppc/pnv_lpc.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) Update v2: add error log message -> https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg05750.html diff --git a/hw/ppc/pnv_lpc.c b/hw/ppc/pnv_lpc.c index d7721320a2..172a915cfc 100644 --- a/hw/ppc/pnv_lpc.c +++ b/hw/ppc/pnv_lpc.c @@ -155,9 +155,15 @@ static void pnv_lpc_do_eccb(PnvLpcController *lpc, uint64_t cmd) /* XXX Check for magic bits at the top, addr size etc... */ unsigned int sz = (cmd & ECCB_CTL_SZ_MASK) >> ECCB_CTL_SZ_LSH; uint32_t opb_addr = cmd & ECCB_CTL_ADDR_MASK; - uint8_t data[4]; + uint8_t data[8]; bool success; + if (sz > sizeof(data)) { + qemu_log_mask(LOG_GUEST_ERROR, + "ECCB: invalid operation at @0x%08x size %d\n", opb_addr, sz); + return; + } + if (cmd & ECCB_CTL_READ) { success = opb_read(lpc, opb_addr, data, sz); if (success) { -- 2.17.2